1. Field of the Invention
This invention relates to photographic optical system protecting devices for cameras, and more particularly to photographic optical system protecting devices suited to cameras of the type in which the spacing between the back cover and the photographic lens is narrow.
2. Description of the Related Art
In the past, in the camera having such a collapsible barrel 19 as shown in FIG. 1, when collapsed (see FIG. 2), the rear vertex 20 of the photographic optical system came very near the back cover 21. In the camera in which the distance between the back cover and the photographic optical system was so much narrow, when the back cover 21 was opened, the possibility of damaging the rearmost lens element of the photographic optical system by a finger touching it was high. Also, as shown in FIG. 3, if the film leader Fa was in curl when the film was loaded, or the exposed film was rewound, a problem would arise that the edge of that film leader scratched the surface of the lens 20. The problems of this sort were not limited to the above-described collapsible barrel type camera, but found in the magnification changeable camera, and their frequency is increasing as the size of the camera is reduced. For example, in the recent lens shutter cameras where the back focal distance is very shortened in order to shorten the total length of the optical system, because the distance between the back cover and the photographic optical system is very narrow similarly to the above-described collapsible barrel type camera, there has been a very high possibility of damaging the lens when the back cover is open or when the film is loaded or rewound.